Discussion and questions related to the course Practical Diesel Tuning
Is there any basic rule to vane position after increasing fuel and boost?
So if I add fuel and boost say to the top end should I then look at opening the vanes a similar % in that area?
What setup are you using Graham? From my experience with boost tuning the turbo needs to maintain a certain vain position to maintain a certain boost level. If you increase fuel then the boost usually increases because there is more energy to drive the turbo.
What i have found in my setup was that as i increased fuel i have to open the vanes up to keep the turbo from over boosting. Depending on the type of turbo ie the factory 1KD turbo in my case im running out of flow and there is too much back pressure even with the vanes completely open. This will be the limiting factor. Im upgrading to a F55V next which should help the situation of too much back pressure.
Hope this helps.
I’m running the stock turbo on my 2.8 Colorado and it seems to track pretty good with about 10% more fuel.
So I will play with opening the vanes up a little at the top fuel quantity where I added the 10% more Pulse Width and see how it goes.
On most of the modern diesel ECM's, desired vane position is only used at idle and light cruise. From there the actuator switches to PID control based on desired boost. Like John said, you'll probably observe the vanes opening at high load to take advantage of the extra exhaust energy. Usually this table needs no adjustment unless you're changing the turbocharger configuration.
Thanks Nick, how do you tell if it’s using a PID for sure? I’m tuning my 2.8 Duramax with Hptuners and in the Vane tab I don’t see anything other than the EGR on/off and mode 1 to 4 tables, looking at my scanner logs in the higher load areas mine seems to close the EGR valve then use the EGR off table which will only open up to 36% at full power.
I see on your YouTube channel you have a GMC Canyon which I’m guessing is the same as my Holden but with more emissions gear.
The easiest way to tell is if the software gives you a table that enables/disables feedforward vane control :). The second easiest way is to compare your boost values to your desired boost table and compare your vane position to your desired vane position and see which control method has the evidence in it's favor. Also, a good clue is: if you see oscillation in the vane position pid it's probably using desired boost.